How to search the source code of the web

Published August 12, 2025 · Basics · 2 min read

Type any string that appears in a page's source — a script URL, a class name, a tracking ID — and get every site that ships it. Add quotes for phrases, OR for alternatives, - to exclude, site:tld to scope, and /regex/ for patterns.

A normal search engine indexes the words a reader sees. Source-code search indexes the code the browser receives — the raw HTML, inline JavaScript, and CSS. That lets you ask questions no keyword search can answer: which sites embed this widget, load this script, ship this exact snippet, or reference this ID. SearchWebCode runs this over the homepage source of ~95M domains and returns the full matched source for every result.

The five things worth knowing

Literal by default. cdn.shopify.com finds every page with that exact string in source. Quote anything with spaces or punctuation: "gtag/js?id=G-".
AND is a space. "wp-content" "gtag" requires both — WordPress sites that also load Analytics.
OR / NOT. "cdn.shopify.com" OR "cdn.bigcommerce.com" matches either platform; "wp-content" -"woocommerce" is WordPress without WooCommerce.
Scope by TLD. Append site:io or site:gov to restrict a market.
Regex for patterns. Wrap in slashes: /UA-[0-9]{4,}-[0-9]/ finds legacy Analytics IDs by shape.

Why full source matters

Every result opens into the complete page source with each occurrence highlighted, so you can tell a real integration from a coincidental substring — the single most common reason a match is a false positive. The full syntax reference has every operator; the technology directory is a good place to see real footprints in action.

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Frequently asked questions

How is this different from Google?

Google indexes the visible words on a page. Source-code search indexes the underlying HTML/CSS/JS, so you can find pages by the code they ship — scripts, widgets, IDs, and snippets a reader never sees.

Do I need to know regex?

No. Most searches are a literal string — a script URL or class name. Regex is there when you want to match a pattern, like an ID format, but it's optional.

What does a result show?

The full source of the matched page with every occurrence highlighted, plus the domain and popularity rank. Viewing source doesn't cost an extra search.